Regenerative furnace.



A. L. STEVENS. REGENERATIVE FURNACE. APPLICATION FILED SEN-25.1916.

Patented Oct. 22, 1918.

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ATTORNEYS A. L. STEVENS.

REGENERATIVE FURNACE.

APPLICATION FILED SEN-25. 191s.

Patented Oct. 22, 1918.

ISHEETS-SHEET 2.

A. L. STEVENS.

REGENERATIVE FURNACE. APPLICAHON FILED SEN-25,1916.

Patented Oct. 22, 1918.

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ATTORNEYS A. L. STEVENS. REGENERATIVE FURNACE. APPLICAIIQN FILEDSEPT-25, 191s.

Patented .Oct. 22, 1918.

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Patented 00t.22,1918.

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A. L. STEVENS. REGENERATIVE FURNACE. APPLICAHON nuzu SEN-25.1916.

Patented Oct. 22, 1918,

YSHEETS-SHEET 6.

INVENTOR ,4 TTOR/VEVS A. L. STEVENS.

REGENERATIVE FURNACE.

APPLICATION FILED SEPL25, 1916. 1,282,649. Patented Oct. 22, 1918.

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INVENTOR f xx lf Y i aluo 4 ATTORNEYS ARTHUR L. STEVENS, OF CHICAGO,ILLINOIS.

REGENERATIVE FURNACE.

Specification of Letters Patent.

Patented Oct. 22, 1918.

Application filed September 25, 1916. Serial No. 122,110.

To all whom it may concern:

Be it known that I, AR HUR L. STEVENS,

a citizen of the United States, residing at Chicago, in the county ofCook and State of Illinois, have invented certain new and usefulImprovements in Regenerative Furnaces, of which the following is aspecification.

My invention relates to the construction of furnaces, more particularlyfurnaces of the regenerative type, and one of the objects of theinvention is to provide certain novel and improved apparatus,inexpensive in its construction and conveniently operated, forcontrolling the fuel and air supply to the combustion chamber andregenerators, and the outflow of products of combustion from the latterby means of which the flow of gases through the furnace may beperiodically reversed, in such manner as to minimize waste of fuel.

A further object is to provide certain improvementsin the constructionof the gas and air valves with a view of economical construction anddurability.

A further object is to provide im roved means for water cooling thedoors of t efurnace.

The invention consists in the new and improved arrangements,constructions and de vices to be hereinafter described and claimed, forcarrying out the above stated objects and such other incidental objectsas will appear from the following description.

The invention is illustrated as embodied in a furnace of preferredconstruction, in the accompanying drawings wherein- Figure 1 is a frontelevation of the furnace.

Fig. 2 is an elevation, with parts in sec tion, of the back of thefurnace.

Fig. S'is a sectional view, on line 3- 3 of Fig. 1.

Fig. 4 is a partial end elevation of the furnace viewing the same fromthe right hand end as shown in Fig. 1.

Fig. 5 is a longitudinal sectional view taken on line 55 of Fig. 3.

Fig. 6 is a fragmentary view, in perspective, illustrating the reversingvalves and their controlling mechanism.

' Fig. 7 is a fragmentary plan view on line 7-7 of Fig. 2. p

Fig. 8 is a fragmentary'longiti-ldinal section taken through one of thegas valves and assoclated mechanisms.

Fig. 9 is a sectional viewon of Fig. 8.

Fig. 10 shows the same parts but in re versed position.

Fig. 11 is a cross sectional view on line 1111' of Fig. 8.

Fig. 12 is a longitudinal section taken through the air valves and theirvalve cas- Figs. 13 and 14 are sectional views on lines 1313 and 14-14,respectively, of Fig. 12, and

Fig. 15 is a detail view of the driving connection between the operatingshaft and the air valve shaft.

Like characters of reference designate like parts in the several figuresof the drawings.

Referring to the drawings, 25 designates the combustion chamber of thefurnace, and

26, 26 the regenerators arranged at opposite sides of the combustionchamber and communicating herewith by fiues 27, 27 The furnace shown inthe drawings is intended to employ gas as a fuel. 28 is the gas supplypipe provided with branches 29. 29 which supply fuel to the burners 30,30 on opposite sides of the furnace through reversing valves, theconstruction of which will be referred to presently. The burnerscommunicate with the combustion chamber by means of ducts 31, 31 whichopen; into the combustion chamber at the places where flues 27, 27communicate therewith.

Air under pressure is supplied to the combustion chamber through theregenerators from air supply pipe 32, branch pipes '33, 33, headers 34,34", and nozzles 3.5, 35* which latter extend through the side walls 36,36 into the spaces 37, 37 under the checkerwork of the regenerators.Reversing valves, to be hereinafter described, are arranged between airsupply pipe 32 and the branchpipes 33, 33.

The products of combustion are discharged from the regenerators throughHues 38, 38 adaptedto be closed by slide valves 39, 39, these fluesleading to a common discharge flue 40 communicating with the stack hecourse of the gases throughthe furnace will be apparent from inspectionof Fig. 5. This figure shows the furnace being i h zll fired from theleft hand side. The gas is introduced into the combustion chamber fromburners through ducts 31 and air is introduced into regenerator 26 frombranch pipe 33, and after being heated by passing through thecheckerwork of the regenerator, is mixed with the gas at the place thatthe two fluids enter the combustion chamber. The products of combustion.flow out through flue 27 regenerator 26 flue 38*, valve 39 being raised,flue 40 and stack draft fiue 41.

By reversing the fuel, air and discharge valves the drafts through thefurnace are reversed. The reversible valve apparatus will now bedescribed.

The reversing calves for the fueZ.-There are two gas valves, one inbranch pipe 29 and the other in branch pipe 29 These valves are alike inconstruction so that it will suffice if the left hand valve (Figs. 2, 6and 8) be described in detail. In the drawing the corresponding parts ofthe other valve are connected by corresponding reference numerals. Thevalve casin connected with pipe 29 is made up prefera 1y of two flanged,tapered, commercial pipe sections 42, 43 suitably clamped together,between which is arranged an apertured'diaphragm 44. The valve 45 is ofthe revoluble damper type-and is mounted upon one section 46 of atelescopic shaft, the other sections being indi--' cated by 47, 48. Thediaphragm plate has a boss 49 to provide a bearing for the shaft section46, and the latter is provided with a collar 50 between which and theboss is interposed a coiled spring 51 which serves to keep the valve,hub 52 of which is pinned to shaft 46, pressed against the diaphragmplate. The shaft section 46 extends through a T pipe section 53 to whichis secured a pipe 54 which connects with the pipe 55 in which theburners 30 are set. The shaft 46 has its outer end squared, as indicatedat 56, a d the squared end of the shaft enters a similarly shaped socketin the connecting member 57 pinned to the shaft section 47,

the latter being similarly connected withshaft section 48 which isrevolubly mounted in bearings formed on a bracket member 58 which issecured to the back wall of the furnace. 59 is an operating shaft,preferably of the same telescopic construction as the gas valve shaftjust .described. .This shaft is mounted in bearings in bracket 58 and asimilar bracket 58 at the other end of the furnace, and is provided withahand wheel 60. Keyed toshaft 48 is the rocking member 61 of amechanical movement similar to a Geneva movement, the revoluble member62 of which is fast to shaft 59. The rocking member is formed with twoarcuate surfaces 63 separated by a slot 64, the arcuate surfaces havingthe same radius as the revoluble member 62 which is cut away at 65 toallow nasaeae the slotted projecting portion of the rocking member topassthe revoluble member. The revoluble member carries a crank 66 provided with a pin 67 which enters the slot 64 of the rocking member. 68is a stop on shaft 59 which, by engagement with a fixed stop member 68limits the rotational movement of the shaft to approximately 300degrees.

Fig. 9 illustrates the position of the parts of the Geneva movement whenvalve 45 is open. Vhen the hand wheel is turned in the directionindicated by the arrows in Figs. 6 and 9, pin 67 of the revoluble memberof the Geneva movement enters slot 64 of the rocking member and rocksthe latter and turns shaft 48, 47, 46 sutliciently to close valve 45. Itwill be understood that valve 45 is closed at this time. The parts ofthe Geneva movement which operate the shaft to which valve 45 is fixed(the right-hand end of Fig. 6) are so positioned that the revolublemember 62 will make a partial revolution after valve 45 has been closedbefore its pin 67 enters the slot 64 in the rocking member 61 When thisoccurs the further turning of the operating shaft 59 opens gas valve 45.An appreciable interval of time intervenes, however, between the closingof valve 45 and the opening of valve 45. During this interval the draftthrough the furnace is reversed, as will be next described. If thereversal of the draft took place while either set of gas burners wasopen, a certain amount of gas would be wasted. By the arrangement abovedescribed this waste is prevented.

Air valves, (Figs. 6 and 12 to 15, inclusive.)The valve casing for theair valves consists preferably of a T pipe section 69 communicating withair supply pipe 32 and conical pipe sections 70, 70*, to the formerofwhich is connected the branch air pipe 33 and to the latter is secureda T pipe section 71 to which branch pipe 33* is connected. Between pipesections 69 and 70, 7 0 respectively, are clamped apertured diaphragms72, 72 against the inner sides of which bear valves 73, 73 74 is a shaftupon which valve 73 is splined and to which valve 73 is pinned. Thisshaft is mounted in bearings 75 formed on the diaphragm plates and in abearing 7 6 formed on the'end cap 77 of the T section 71. 7 8 is acollar pinned to shaft 74 and formed with a spring seat 79 for a coilspring 80 which bears against the hub 81 of valve 73, thereby keepingboth valves pressed closely against their respective diaphragm plates.On the end of shaft 74 is a sector gear 82 which mesheswith a pinion 83on the operating shaft 59. As shown in Figs. 12, 13' and 14, the airvalve 73 is open and air valve 7 3 closed. The air, therefore,

enters the furnace through regenerator 26 and flue 27 as shown by thearrows in Figs. 2 and 5. When the operating shaft is re fineness volvedta the gas valves the position of the air valves is also reversed sothat the air is shut ofi from regenerator 26 and admitted to regenerator26*, causing a reversal of the draft through the furnace. The air valvesare moved simultaneously, one beginning to open and the other beginningto close as soon as the operating shaft 59 is revolved. The reversal ofthe air, therefore, is practically complete before gas valve has begunto open, effecting the economy in fuel above noted.

The valves 39, 39 controlling the discharge of products of combustionfrom the regenerators are also preferably operated from shaft 59 whichis provided with drums 84, 84?, upon which are Wound the cables 85, 85attached, respectively, to valves 39, 39 'With the furnace firing fromthe left hand side, as shown in the drawings, valve 39 will be closedand valve 39 opened. The position of the valves is reversed when theshaft 59 is turned-to reverse the gas and air valves.

D00rs.-The front wall 86 of the furnace is formed with a plurality ofdoor openings 87 which are closed by doors 88 each of which is supportedby a cable 89 attached to a sector 90 pivoted at 91 to a bar 92extending across the front of the furnace. The

sector has a rigid arm 93 connected by a.

cable 94 with one arm 95 of a bell crank pivotally mounted on a bracket96, the other arm 97 of which is considerably longer than arm 95 and hasconnected thereto by cable 98 a counterweight 99. The doorin closedposition rests upon a casting 100 on the front of the furnace.

Each door is formed with a water space 101 intowhich' projects,

slidably, a water feed pipe 102 connected with a water supply chamber103 on the front of the furnace which is kept constantly supplied withwater through pipe 104. The doors are provided with water outlet pipes105 which extend, slidably, into vertically disposed branch pipes 106connected with a discharge pipe 107 on the front of the furnace whichruns to any suitable drain. It will be observed that the water pipes, bymeans of which circulation is maintained through the water spaces of thedoors, serve also to guide the doors when they are raised and lowered.

While I have described my invention in certain preferred embodiments, itwill be understood that changes in the design and arrangement of theparts might be made without departure from the principles of theinvention. Therefore I do not wish to be understood as limiting theinvention to the precise constructions, arrangements and devices shownanddescribed except so far as the claims are specifically so limited.

I have referred to the burners 30 and 30 as constituting two sets ofburners, as ordinarily there will be more than one burner on each sideof the furnace. i do not wish to imply, however, that it is necessary incarrying out my invention to have a plurality of separate burners ineach so-called set.

ll claim:

1. YA valve reversing system for regenerative furnaces comprising fuelvalves for controlling the fuel supply to alternately utilized sets ofburners, and mechanism for operating said valves consisting of a shaftand Geneva movements associated with said shaft and with the valves,respectivel ,timed so as to shift said valves one a er the other. r

2. A valve reversing system for re enerative furnaces comprising fuelvalves or controlling the fuel supply to alternately utilized sets ofburners, and mechanism for operating said valves consisting of a shaftand Geneva movements associated with said shaft and with the valves,respectively, timed so that the closed valve is not opened until anappreciable period of time after the open valve is closed.

3. A valve reversing system for a regenerative furnace havingregenerators, a combustion chamber communicating with said regenerators,and a fuel supply pipe having branches entering the combustion chamberat difierent points comprising valve casings associated with saidbranch'pipes provided with apertured diaphragms, revoluble damper valveswhich bear against said plates and close said apertures, telescopicshafts to which said valves are fixed, an operating shaft, and drivingconnections between said operating shaft and the shafts to which thevalves are fixed.

4:. A valve reversing system for a regenerative furnace havingregenerators, a combustion chamber communicating with. saidregenerators, and a fuel supply pipe having branches leading to thecombustion chamber comprising valve casings associated with said branchpipes provided with apertured diaphragms, revoluble damper valves whichbear against said plates and close said apertures. telescopic shafts towhich said valves are fixed, an operating shaft, and drivin connectionsbetween said operating she and the shafts to which the valves are fixeddisposed so that an appreciable period of time elapses after the openvalve has been closed before the closed valve is opened.

5. A valve reversing system for a regeneratiye furnacehavingregenerators, a combustion chamber communicating with saidregenerators, and a fuel supply'pipe having branches leading to the'combustion chamber comprising valve casings associated with said branchpipes provided with apertured diaphragms, revoluble damper valves whichbe 1' against said plates and close said apertu es, telescopic shafts towhich said valves are fixed, an operating shaft, and Geneva ionmovements associated with said shaft and with said valves, respectively,timed so that an appreciable interval of time elapses after the openvalve is closed before the closed valve is opened.

6. In a regenerative furnace, the combination with the regenerators, acombustion chamber communicating with said regenerators, two sets ofalternately utilized fuel burners to supply fuel to the combustionchamber, a fuel supply pipe and air pipes leading to said regenerators,respectively; of reversing valve apparatus comprising fuel valves forcontrolling the fuel supply to the burners, valves for controlling thesupply of air to the regenerators, and mechanism for operating saidvalves whereby the flow of fuel is shut off from the furnace while thedraft through the combustion chamber is being reversed.

7. In a regenerative furnace, the combination with the r'egenerators, acombustion chamber communicating with said regenerators, two sets ofalternately utilized fuel burners located to supply fuel to thecombustion chamber, a fuel supply pipe and air pipes leading to saidregenerators, respectively; of reversing valve apparatus comprising fuelvalves for controlling the fuel supply to the burners, valves forcontrolling the supply of air to the regenerators, and mechanism foroperating said valves whereby the initial movement of such mechanismcloses the open fuel valve, the continued movement thereof closes oneair valve and opens the other, and the completion of said movement opensthe other fuel valve.

8. In a regenerative furnace, the combination with the regenerators, acombustion chamber communicating with said regenerators, two sets ofalternately utilized fuel burners located to supply fuel to thecombustiou'chamber, a fuel supply pipe, and aiil pipes leading to saidregenerators, respectively; of reversing valve apparatus comprising fuelvalves for controlling the supply of fuel to the burners, air valves forcontrolling the flow of air to the regenerators, and mechanism formoving said valves which operates continuously on the air valves to openone and close the other but intermittently on the fuel valves so that anappreciable period of time elapses after the open fuel valve is closedbefore the pther fuel valve is opened.

9."In a regenerative furnace, the combination with the regenerators, acombustion chamber communicating with said regenerators, two sets ofalternately utilized fuel burners, a fuel supply pipe, and air pipesleading to said regenerators, respectively; of reversing valve apparatuscomprising fuel valves for controlling the supply of fuel to theburners, air valves for controlling the air to the regenerators,respectively, an

leading let ports, a

operating shaft, driving connections between the operating shaft and theair valves whereby one valve is opened and the other closedsimultaneously, and driving connections between the operating shaft andthe fuel valves timed so that an is closed before the'closed valve isopened.

10. In a. regenerative furnace, the combination with the regenerators, acombustion chamber communicating with said regenerators, two sets ofalternately utilized fuel burners to supply fuel to the combustionchamber, a fuel supply pipe, and air pipes to said regenerators,respectively, of reversely valve apparatus comprising fuel valves forcontrolling the supply of fuel to the burners, air valves forcontrolling the air to the regenerators, respectively, an operatingshaft, driving connections between the operating shaft. and the airvalves whereby one valve is opened and the other closed simultaneously,and Geneva movements associated with said op erating shaft and with thefuel valve respectively, timed so that the closed valve is not openeduntil after the open valve is closed.

11. In a regenerative furnace, the combination with the regenerators, acombustion chamber communicating with said regenerators, a fuel supplypipe having branches leading to the combustion chamber, an air supplypipe having branches leading to the regenerators respectively; ofreversing va lye apparatus comprising fuel and air. valves to controlthe flow of fuel and airthrough said branch pipes respectively, andmechanism, for operates toreverse the draft through the furnace whilethe gas is shut off therefrom.

12. In a regenerative furnace, the combination with the 'regeneratorshaving outcombustion chamber communicating with said .regenerators, two

appreciable period of time elapses after the open'valve shifting saidvalves which sets of alternately utilized fuel burners to supply fuel tothe combustion chamber, a fuel supply pipe, and air pipes leading tosaid regenerators respectively; of reversing valve apparatus comprisingfuel valves for controlling the fuel supply to the burners, valves forcontrolling the supply of air to the regenerators, valves for openingand closing said outlet ports, and mechanism for operating said valveswhereby the flow of fuel is shut off from the furnace while the draftthrough the combustion chamber is being reversed.

13. In a regenerative furnace, the combination with the regeneratorsformed with outlet ports, a combustion chamber communicating with saidregenerators, a fuel supply pipe having branches leading to thecombustion chamber, an air supply pipe having branches leading to theregenerators respecii sly mesh Whisk @3333 21 Iurmcs 9.51 the sombus afurnace selynrising reveair Yalves, hcah l movabie 00mm parts an ops/mti-011s between csmbinatien with "12 valves, an spam c pvsmsms Fran saldvalves aims-c1 s0 said valves is clsssd after all clabls ntsr'm theother valve is mansfi.

36c ins combination 9. a

:mrnase having ssparst-e fuel 2111 air supsims leading; the regam;

erefor, 01-

i'cr "5sair ihrmagh f1 1 valves 23s close a Hive g ens1 21.30 rs.embust-wn 1'; sass 0; aitsmabeiy utilize parts entering; the combusztlonchamber mats s .1 i at 'clmeisnis palms, um. supply ipes leadsaid portsair p5. as leading said Tsgsnerbtors, valves for eontl Qihnp; the fuelfuel wives are dsssvlo 18. In combination, a regenerative furnace hzwmgregsnsmtors, a combustion chamber, two seis of alternately utilized fuelports entering the combustion chamber difi'ersnt points, ills supplypipes leading to said ports, air pipes Keading to said regensmtm s,valves 1E0 csntmliing sh-s fuel and air sup cdy and mechanism formissing iwbh the 5511s vsivss duymg z'eversai 01' the L, STEVENS"

